Impulse coil system for transmitting shock wave through stationary rod

ABSTRACT

A mechanical shock signal is applied to a stationary shocktransmitting rod from an impulse coil system in which a fixed short circuited disc is connected to the bottom of the rod and has current induced therein from an adjacent stationary primary winding which is energized by a capacitor discharge. A plurality of such systems have primary windings connected in a series so that simultaneous shock forces are transmitted through the spaced rods as for the simultaneous operation of blast valves of the poles of a high voltage circuit breaker.

United States Patent lnventor Otto Jensen Malvern, Pa.

Appl. No. 792,975

Filed Jan. 22, 1969 Patented Jan. 26, 1971 Assignee l-T-E ImperialCorporation Philadelphia, Pa. a corporation of Delaware IMPULSE COILSYSTEM FOR TRANSMITTING SHOCK WAVE THROUGH STATIONARY ROD 6 Claims, 2Drawing Figs.

U.S. Cl 307/108, 317/143, 173/117 Int. Cl .7 1-103k 3/00 Field ofSearch317/143,

151; 307/108; 318/1 14, 135; 173/1 17(lnquired); 81 1/52.3; 200/310Primary Examiner-Robert S. Macon Assistant ExaminerH. .l. HohauserAttorney-Ostrolenk, Faber, ierb & Soffen ABSTRACT: A mechanical shocksignal is applied to a stationary shock-transmitting rod from an impulsecoil system in which a fixed short circuited disc is connected to thebottom of the rod and has current induced therein from an adjacentstationary primary winding which is energized by a capacitor discharge.A plurality of such systems have primary windings connected in a seriesso that simultaneous shock forces are transmitted through the spacedrods as for the simultaneous operation of blast valves of the poles of ahigh voltage circuit breaker. I 1

1 IMPULSE COIL SYSTEM on TRANSMITTING SHOCK WAVE THROUGH STATIONARY nonThis invention relates to shock force transmission systems, and moreparticularly relates to a static force-transmitting system in whichahammer blow is applied to one end of a force-transmitting rod by thefixed short circuited winding of an impulse coil system.

Many application are well knownin which a shock force is transmittedthrough a rod in order to. transmit an operating force from one end of arod to a movable mass seated on the opposite end of a rod. Systems ofthis type are used in high voltage air blast circuit breakers in'whichthe interrupter is mounted at the top of an insulation pillar andcontains a movable blast valve which must be opened at a highlyaccurately controlled time. A plurality of such units are commonlyprovided to form multipole assemblies where it is necessary that theblast valves of each pole be operated as close to simultaneously aspossible. In such arrangements, an operating means for applying a hammerblow to the bottom end of a rod is needed to provide a shock wave in therod which is carried to the valve in order to open the blast valve. Atypical means for applying this hammer blow is a solenoid plunger foreach 'of the rods with the windings for each of the solenoids connectedin series. The energization of the windings drives their respectiveplungers into contact with the lower ends of the rods so that shockwaves are transmitted by the rods and the shock wave energy is appliedto the blast valves at the tops of the rods. The solenoid mechanisms ofthis type arrangement have slight inherent differences which are almostimpossible to control during manufacture and duri'ng'operation.Therefore, it is almost impossible to obtain the simultaneoustransmission of shock waves along the rods of'the system. Moreover, suchsolenoid-operating mechanisms are bulky and expensive, and the use ofmovable components affects the reliability of the system.

Attempts have been made to use the movable winding of an impulse coilarrangement to apply the hammer blow to the end of one or more rods toinduce a shock wave in the rods. Again,howeve'r, because the movablewinding had to travel over'a relatively long distance before strikingthe bottom of the rod, it has been diffIcult to obtain simultaneousaction for each of the rods and the need for winding movement affectsthe reliability of the system as in the case of solenoid arrangement.

In accordance with the present invention, it has been found that theshort-circuited winding of an impulse coil system can be connecteddirectly to the end of a shock-transmitting rod, whereby theenergization of the primary winding will cause the short-circuitedwinding to induce a shock wave in the rod without requiring movement ofthe winding into the end of the rodq-With this novel arrangement, itwill be apparent that the reliability of the system is improved,sincethere is no need for substantial motion of the short-circuitedwinding. Moreover, where a plurality of rods are used with a pluralityof such im pulse coil systems, the shock waves in the rods are appliedvirtually simultaneously to the ends of the rods. That is, since thereis no need for movement of the short-circuited winding, the shock forcesfor each of a plurality of rods start virtually simultaneously and reachthe movable mass at the top of the rods virtually simultaneously.

Accordingly, a primary object of this invention is to provide a staticshock force system for shock-transmitting rods.

- Another object of this invention is to improve the reliability of ashock force-transmitting system.

*A still further object of this invention is to provide a novel shockforce system for a plurality of shock-transmitting rods in which shockforces are applied to the rods virtually simultaneously.

These and other objects of the invention will become'apparent from thefollowing description which is taken in connection with the drawings inwhich:

- FIG. I is a partial cross-sectional view of a shock forcetransmittingsystem for a single shock force rod when using the impulse coilarrangement of the present invention.

rality of rods which may be each connected to the blast valve of arespective high voltage circuit interrupter.

Referring first to FIG. I, there is shown therein a shock'force-transmitting rod 10 which is shown as a hollow, rigid rod whichcould have an inside diameter of three-eights inch, an outside diameterof fifteen-sixteenths inch, and any desired length, depending upon theparticular application. Rod 10 may be made of Melamine glass or anyother suitable relatively rigid material which could efficiently conductshock waves. A mass 11 is seated at top of rod 10 and is movable awayfrom the top of rod 10 in the direction of arrow 12. The ma'ss'll may beany desired mass which is to be mechanically moved by a shock forceconducted by the rod 10. For example, mass 11 may be a blast valvehaving a mass of about l25 grams,

. which is to be moved about l4 mm in l millisecond. Note that rod 10 isstationarily mounted to any suitable mounting support, schematicallyillustrated by the hatched lines 13.

An impulse coil system 14 is then provided at the bottom of rod 10 andconsists'of a conductive disc 15 which serves as a short-circuitedwinding coupled to a multiturn primary winding 16. The disc 15 may bedirectly secured to the bottom of rod 10, although satisfactory resultshave been obtained when a spacing of about mils exists between disc 15and rod 10. Short-circuited winding 15, winding l6 and rod 10 are eachconcentric with axis 17 of rod I0 and winding I6 is stationarily mountedas schematically illustrated by the hatched lines 18.

A discharge circuit 19 is then connected in series with primary winding16 and consists of a transformer 20 connected to a suitable AC source,with the transformer secondary Wind'- ing connected through rectifier 21to charge energy storage capacitor 22. A diode 23 may be connected asshown in copending application Ser. No. 754,334, filed Aug. 21, 1968,

now US. Pat. No. 3,530,304, in the name of Felix H. Bachofen, entitledDriving Circuit For Impulse Coils With Capacitor-shorting Switch, andassigned to the assignee of the present invention (C-l457(ER) where thediode 23 prevents reversal of voltage across capacitor 22 and increasesthe force of repulsion between winding 15 and 16 when discharge switch24 is closed.

In one typical arrangement, capacitor 22 was a 200 microfarad capacitorwhich is charged to 1,000 volts. Winding 16 was a spiral-wound coilhaving 25 turns. The short-circuited winding 15 consisted of a disc ofcopper having a 'diameterof 1% inches and a thickness of one-fourthinches.

The disc 15 was fixed directly to the bottom of tube 10 in some casesand in other cases was spaced from the bottom of tube 10 by an air gapof about 40 mils.

In operation, when switch 24 is closed, capacitor ,22 discharges throughwindings 16.The high current discharge in winding 16 induces acirculating current in disc 15 which gives rise to a highelectromagnetic force of repulsion between windings l5 and 16. Winding15 is substantially fixed, whereby this force of repulsion is applied torod 10 as an impulse force which travels through rod 10 as a shock wavewith the speed of sound in rod 10. When the shock waveenergy reachesmass 11, it moves upwardly in the direction of arrow 12 by virtue of thetransfer of energy from rod 10 to mass 1 1.

Referring next to FIG. 2, the invention is illustrated in connectionwith three solid shock-transmitting rods 30, 31 and 32 which each havemovable masses 33, 34 and 35, respectively, at their tops. Movablemasses 33 to 35 could, for example, be blast valves of separately housedhigh voltage interrupters positioned at the top of a pedestal insulator.In such an application, it is essential that the blast valves beoperated simultaneously or as close to simultaneously as possible.Accordingly, each of rods 30 to 32 have a short-circuited winding membersuch as members 36, 37 and 38 mounted adjacent their respective bottoms.Primary windings 39, 40 and 41 are then located below short-circuitedwindings 36, 37 and 38, in the manner previously described in connectionwith FIG. 1. Windings 39, 40 and 41 are then connected in series withcharging circuit 19, which is similar to the charging circuit 19 of FIG.1.

In operation, capacitor 22 will, when switch 24 is closed. dischargethrough series connected windings 39, 40 and 41, thereby imparting asimultaneous force to the short-circuited windings 36, 37 and 38 so thata shock wave is started in each of rods 30, 31 and 32 at virtually thesame time. Therefore, as suming that rods 30, 31 and 32'have the sameshock wave transmission characteristics, the shock wave will reach blastvalves 33, 34 and 35 at the same time so that the valves will beoperated simultaneously.

Although this invention has been described with respect to particularembodiments, it should be understood that many variations andmodifications will now be obvious to those short-circuited windingmounted against substantial movement in an axial direction andpositioned immediately adjacent said other end of said elongated rod;and circuit means I for applying a current through said primary windingwhereby an impulse force is applied to said other end of said elongated,rod due to the force of repulsion between said short-circuited windingand said primary winding, which force creates a shock wave in said rodwhich is applied to said movable mass.

2. The device as set forth in claim 1 wherein said short-circuitedwinding comprises a metallic disc.

3. The device as set forth in claim 1 wherein said circuit meansincludes a capacitor and means for charging said capacitor.

4. An operating system for substantially simultaneously applying a forceto a plurality of movable masses; said system comprising a plurality ofelongated rods of rigid material, one end of each of said rodspositioned adjacent a respective one of said plurality of movablemasses, and respcctive impulse coil means positioned adjacent the otherend of each of said rods; each of said impulse coil means comprising ashort-circuited winding and a primary winding electromagnetic'allycoupled thereto; each of said short-circuited windings mounted againstsubstantial movement in an'axialdirection and positioned immediatelyadjacent said other end of its said respective elongated rod; anddischarge circuit means connected to each of said primary windings forapplying a pulse current through said primary windings, whereby animpulse force is applied to said other ends of each of said elongatedrods and shock waves are conducted through'said elongated rods to saidmovable masses.

5. The system of claim 4 wherein said primary windings are connected inseries with one another and with said discharge circuit means.

6 A force-transmitting device for transmitting a force from a firstregion to a second region comprising in combination: an elongated rod ofrigid material having first and second ends disposed adjacent said firstand second regions, respectively, a conductive disc positioned adjacentsaid one end of said elongated rod and in contact with said one end ofsaid elongated rod, and an electrical circuit means adjacent saidconductive disc operative for inducing a high current in said disc and arepulsive impulse force between said conductive disc and electricalcircuit means, and means for stationarily mounting said elongated rodand said conductive disc.

1. An impulse force-operating device comprising an elongated rod ofrigid material, a movable mass positioned adjacent one end of said rodand an impulse force means positioned adjacent the other end of saidelongated rod; said impulse force means comprising a short-circuitedwinding and a primary winding electromagnetically coupled thereto; saidshort-circuited winding mounted against substantial movement in an axialdirection and positioned immediately adjacent said other end of saidelongated rod; and circuit means for applying a current through saidprimary winding whereby an impulse force is applied to said other end ofsaid elongated rod due to the force of repulsion between saidshortcircuited winding and said primary winding, which force creates ashock wave in said rod which is applied to said movable mass.
 2. Thedevice as set forth in claim 1 wherein said short-circuited windingcomprises a metallic disc.
 3. The device as set forth in claim 1 whereinsaid circuit means includes a capacitor and means for charging saidcapacitor.
 4. An operating system for substantially simultaneouslyapplying a force to a plurality of movable masses; said systemcomprising a plurality of elongated rods of rigid material, one end ofeach of said rods positioned adjacent a respective one of said pluralityof movable masses, and respective impulse coil means positioned adjaCentthe other end of each of said rods; each of said impulse coil meanscomprising a short-circuited winding and a primary windingelectromagnetically coupled thereto; each of said short-circuitedwindings mounted against substantial movement in an axial direction andpositioned immediately adjacent said other end of its said respectiveelongated rod; and discharge circuit means connected to each of saidprimary windings for applying a pulse current through said primarywindings, whereby an impulse force is applied to said other ends of eachof said elongated rods and shock waves are conducted through saidelongated rods to said movable masses.
 5. The system of claim 4 whereinsaid primary windings are connected in series with one another and withsaid discharge circuit means.
 6. A force-transmitting device fortransmitting a force from a first region to a second region comprising,in combination: an elongated rod of rigid material having first andsecond ends disposed adjacent said first and second regions,respectively, a conductive disc positioned adjacent said one end of saidelongated rod and in contact with said one end of said elongated rod,and an electrical circuit means adjacent said conductive disc operativefor inducing a high current in said disc and a repulsive impulse forcebetween said conductive disc and electrical circuit means, and means forstationarily mounting said elongated rod and said conductive disc.